Gas cutting prevention in revolver firearms



June 9, 1964 D. w. CHARRON GAS CUTTING PREVENTION IN REVOLVER FIREARMS 2Sheets-Sheet 1 Filed March 9, 1962 Dwayne? Cfiarram A RNEY June 1964 D.w. CHARRON GAS CUTTING PREVENTION IN REVOLVER FIREARMS 2 Sheets-Sheet 2Filed March 9, 1962 INVENTOR ORNEY United States atent 3,136,084 GASCUTTING PREVENTION IN REVULVER FIREARMS Dwayne W. Charron, Chicopee,Mass, assignor to Smith This invention relates to firearms, and moreparticularly to firearms of the revolver type. The invention increasesthe strength, endurance, and working life of the firearm.

In revolver firearms, the cylinder has formed therein a plurality ofchambers for receiving cartridges. The cylinder rotates in the frame tosuccessively present the chambers to the barrel. Such revolvers havegenerally been constructed with a clearance space or gap between therear end of the barrel and the cylinder. After a shot is fired, and theexplosion of the propellant material in the cartridge has moved thebullet out of the chamber into the barrel, the expanding gases escapethrough this gap. When cartridges are used having large quantities ofpowder, the propellant gases, by their heat and velocity,

tend to erode those portions of the frame which they contact. Thiserosion of the frame causes a weakening of the frame which can result inthe breaking or failure of the frame, rendering the firearm useless andperhaps injuring the shooter or operator.

The present invention resides in the concept of providing a hard,erosion-resistant portion in the frame adjacent to the gap between thebarrel and cylinder. This erosion-resistant portion can be an insertthat is made substantially harder than the remainder of the frame.Thereby, the hardened portion resists the abrasion of the propellantgases. Also, the working life and safety of the firearm are increased.Further, the remainder of the frame can be made less brittle than theharder portion so as to reduce the danger of the frame being broken ondropping.

For a better understanding of the invention and its other objects,advantages, and details, reference is now made to the presentlypreferred embodiment of the invention which is shown, for purposes ofillustration only, in the accompanying drawings.

In the drawings:

FIGURE 1 is a side elevation of a revolver having an abrasion-resistantinsert in the top strap according to the invention;

FIGURE 2 is an enlarged, fragmentary, partially broken-away view of thecylinder and a portion of the barrel and frame of the revolver shown inFIGURE 1;

FIGURE 3 is a fragmentary section, similar to the upper portion ofFIGURE 2, and showing the firearm just after a shot has been fired andthe bullet is being propelled through the barrel and propellant gasesare escaping through the gap between the barrel and cylinder;

FIGURE 4 is an enlarged fragmentary section of the upper portion ofFIGURE 3, showing the paths of the escaping gases;

FIGURE 5 is a fragmentary perspective looking up at the top strap andforward portion of the frame of a conventional revolver; I

FIGURE 6 is a view similar to FIGURE 5 showing a groove milled out ofthe top strap after the first step of the process of the invention;

FIGURE 7 is a sectional view on line 77 of FIG- URE 6;

FIGURE 8 is a view like FIGURE 6 after a welding rod of heat-hardenablealloy has been welded in place in the groove in the top strap;

FIGURE 9 is a sectional view along line 9-9 of FIGURE 8;

FIGURE 10 is a perspective view similar to FIGURE 8 after the weldedinsert has been machined to form a flush surface for the top strap; and

FIGURE 11 is a section along the line 11-11 of FIGURE 10.

Briefly stated, in the embodiment of the invention illustrated in thedrawings, a groove is formed in the top strap that extends over thecylinder and bridges the gap between the cylinder and the barrel. Thegroove is formed at the gap. A heat-treatable alloy, capable ofachieving great hardness, is Welded into the groove to form an insert.The entire firearm is then heat-treated, as by austempering, in order toincrease the hardness of the frame and increase the hardness of theinsert to a value substantially greater than that of the frame. Thereby,sulficient hardness is provided, in the insert, at the position wherenecessary. In the remainder of the frame, such hardness would beunnecessary and undesirable in that it would also be accompanied bybrittleness which would make the frame too readily breakable on droppingor other impact.

In FIGURE 1 there is illustrated a revolver including the conventionalframe 20, grip member 21, trigger 22., and hammer 23. The frame andother parts can be formed of various materials such as steel, aluminum,and others suitable for the purpose intended. Cylinder 24 is rotatablymounted in the frame 20 and has a plurality of spaced chambers 25 formedtherein.

A barrel 26 has its rear portion 28 threadedly received in an opening inthe yoke 30 of the frame 20. A gap or clearance space 32 is formedbetween the rear surface 34 of the barrel 26 and the front surface 36 ofthe cylinder 24.

As seen in FIGURE 2, each chamber 25 has an enlarged rear end forreceiving a cartridge 38 having a large quantity of propellant powdertherein.

The frame 20 includes a top strap 40 extending rearwardly from the yoke30 to the back portion 42 and bridging the gap 32.

The frame 20 can be formed of a steel known as Society of AutomotiveEngineers designation number 1035 containing 0.32 to 0.38 percent byweight carbon; 0.60 to V 0.90 percent by weight manganese; a maximumpercent Element: Percent by weight Carbon 0.85 Chromium 4.15 Manganese0.30 Vanadium 1.95 Molybdenum 5.0 Silicon 0.3 Tungsten 6.4

The insert 46 is provided in the top strap and the frame 20 is then heattreated so as to bring the hardness of the frame to a hardness of aboutRockwell C hardness number 20 and the insert 46 to a hardness of aboutRockwell C number 61 to 63.

The measurement of the hardness by the Rockwell test is described inAmerican Society of Testing Materials designation B 18-42. According tothe Rockwell C test, a. standard diamond point is pressed into thematerial under a load of ten kilograms. The load is thereafter increasedto kilograms and the increased penetration Patented June 9, 1964.

for the increase in load'is measured in terms of the Rockwell C hardnessnumber. This hardness number indicates the materials capacity forresisting abrasion and cutting. 1 t

' A process of the invention wherein, the insert 46 is formed in the topstrap 49 is shown in FIGURES to .10. In FIGURE 5, there is illustrated aportion of a conventional revolver frame having a threaded opening 515for receiving the rearend of the barrel 26, and including the top strap40. As viewed in FIGURE 6, the top strap is milled out to form atransverse groove 52 at a position adjacent the gap 32 between thebarrel and cylinder in the assembled revolver. Thereafter, a weld rod,having the composition previously described for insert 46, is weldedinto the groove 52. During the weld ing, the rod achieves a temperatureof about 2430 degrees Fahrenheit. The rod forms a rough'insert'54 seenin FIGURES ,8 and '9. This heating and cooling 'of'the rod, occurringduring welding, produces some increase in the hardness of the roughinsert.j 7

Next, the frame can be heat-treated by austempering wherein thetemperature of the'frame is raised to about 1800 degrees Fahrenheit,heat-soaked at this temperature and then quenched in oil. After thesesteps, the insert 54 has achieved a hardness of about Rockwell Chardness number 62 and the remainder of the frame has achieved ahardness of about Rockwell C number 20.

- 3. In a revolver firearm having a frame, a barrel, a 7

cylinder rotatably mounted in said" frame, said cylinder having aplurality of chambers formed therein for receiving cartridges, therotation of said cylinder bringing said chambers successively intoalignment with said barrel, the forward end of said cylinder beingspaced from i the rear end of said barrel by a gap through whichpropellant gases from said cartridgespass, said frame having a top strapbridging a part of said gap between said barrel and said cylinder; theimprovement which comprises said 7 top strap having a portion at saidgap that is substantially harder/than the remainder of the frame forresisting erosion by said propellant gases, said gap being open for thepassage of said gases outwardly through said gap to the space aroundsaid barrel and cylinder'so 1 that a portion of said gases contacts saidharder bridging 7 top strap portion;

Next, the rough insert 54' has its extending portion machined off toform the flush surface 58 of insert 46 shown in FIGURESIO and 11. I

The harder top strap portion can also be produced by localized heattreating of atleast a portion of an integral top strap at the gap 32.

Thus, the invention provides a process of making a revolver having aportion, at the gap between'the cylinder and barrel, that is resistantto cutting by the gasses pro.-

duced by each shot.

-While presently preferred'embodiments of the invention have beenillustrated and described, it will be recognized that the inventionfcanbe otherwise variously embodied and practiced within the scope of thefollowing claims.

I claim: a

a l. In a revolver firearm having a frame, a barrel, a' cylinderrotatably mounted in said frame, said cylinderhaving a plurality ofchambers formed therein for receiving cartridges,'the rotation of saidcylinder bringing said chambers successively into alignment with 'saidbarrel, the forward end of said cylinder being spaced from'the rear endof said'barrel by a gap through which propellant gases fromsaidfcartridges pass; the impro'vernent which comprises said framehavinga portion bridging a'part of said gap between said barrel and said'cylinderfsaid bridging portion being subst'antiallyharderthan theremainder of the frame for resisting erosion by saidpropellant gases,said gap being open for the passage of said gases outwardly through saidgap to the space aroundjsaid barrel and cylinder so that a portion ofsaid gases contacts said harder bridging frame portion;

2. Ina revolver -firearm having a frame, a barrel, :a cylinder rotatablymounted in said' frame, said cylinder having a plurality of chambersformed therein for receiving cartridges, the rotation of saidcylinderbringingsaid chambers successively into alignment with'saidbarrel, the forward end of said cylinder. being spaced from the rear endof said barrel by a gap through which propellant gases from,saidcartridges pass; the improvement which; comprises said frame havinga portion bridging a part of said gap between said barrel andsaid-cylinder, said '7 rear endof said barrel by a'gap through whichpropellant gases from said cartridges passpfsaidframe including aElement 4. In a revolver firearm having aframe, a barrel, a

cylinder rotatably mountedin saidframe,.said cylinder having a pluralityof chambers formed therein for receivj ing cartridges, the rotation ofsaid cylinderbringing said chambersrsuccessively into alignment withsaid barrel, the

7 forward endof said cylinder being spaced from the rear 'end'of saidbarrel by a gap through which propellant gases from said, cartridgespass, said frame including "a top strap extendingracross a part of saidgap -between said barrel and said cylinder; the improvement whichcomprises said frame being formed of a steel of 'about'Rock-t well (Ihardness number 20, said top strap having an inl serttherein, at saidgap, formedrof'a steel having a hardness of about Rockwell C number 62',said insert resist v ing erosion by'said' propellant gases, said gapbeing open for the passa'geof said gases outwardly through said gaptothespace around said barrel and cylinder so'that' a 7 portion 'of saidgasescontacts said harder insert.

5. In'a revolver fireariniihavi'ng a frame, a barr'elja cylinderrotatably mounted-in said frame, said' cylinder having a pluralityiofchambers formed therein for receiva .ing cartridges, the rotation ofsaid cylin der bringing said,

chamberssuccessively into alignment with said barrel, the forward endiofsaid cylinder being spaced from the top' strap extending across a partof said gap between said barrel and said cylinder; the improvement whichcom-. prises said framebeing formedof SAE. steel 'designation i No.11035 and having athardness of about Rockwell C" hardness number20,.said top; strap havingian' insert thereiron andfincluding thefollowing components:

: in, at said gap, formed'of a steel composed principally of is Percentby-weight, Carbon Chromium ness number 62, said insert resisting erosionby'said pro pellant gases; said gap being openfor the. passage ofsaidbridging portion being formed of substantially harder f 1 material thanthe'remainderofthe frame for resisting erosion 'by said propellantgases, said gap being openlfortion of said gases portion.

the passage of said gases outwardlythroug'h s aid gap to T the spacearound said barrel and cylinder so thata'porcontacts said harderbridging-frame 1 gases foutwardly through said gap to thespace aroundsaid" barrel and cylinder'so that a portion of gases contacts saidharder-insert; l

j :6. In aprocess for makingarevolvervfirearm, theisteps;fl formingagroovef intthatportiomof the revolver'which bridges a part ofthe gapbetween the" barrel and ,the

cylinder and is". contacted by part of the" gases passing through saidgap, to ithe iatmosphere'j surrounding ithe' re volver; filling, the.groove' with a, 'materi'althat' can be heat-treated'to a hardnesssubstantially fgreatertharifthe frame; and,"'heat-treating the materialto makesaid insertf substantiallyh arder .thansaid frame whereby vsaidharder? said insert having a hardness of, about ,Rockwellhard a '1material resistserosion by said propellant gases which contact it.

7. In a process for making a revolver firearm, the steps: forming agroove in the top strap of the frame, said top strap bridging a part ofthe gap between the barrel and the cylinder and contacted by a part ofthe gases passing through said gap to the atmosphere surrounding therevolver; welding a rod into said groove to form an'insert, said rodbeing formed of steel that is heat-treatable to a hardness substantiallygreater than the frame, said rod steel being composed principally ofiron and including the following elements in about the followingamounts:

raising the temperature of the frame and insert to about 6 1800 degreesFahrenheit; heat-soaking the frame and insert at said temperature; and,quenching the frame and insert to make the insert substantially harderthan said frame; whereby said harder insert resists erosion by saidpropellant gases which contact it.

References Cited in the file of this patent UNITED STATES PATENTS1,346,188 Fahrenwall July 13, 1920 1,346,189 Fahrenwald July 13, 19201,961,520 Malcolm June 5, 1934 1,982,421 Emmons Nov. 27, 1934 2,090,656Williams Aug. 24, 1937 2,104,319 Dicke Jan. 4, 1938 2,324,775 HentschelJuly 20, 1943 2,342,703 Simpson Feb. 29, 1944 2,499,944 Brace et a1.Mar. 7, 1950 2,847,786 Hartley et a1. Aug. 19, 1958 2,863,248 Koucky eta1. Dec. 9, 1958 2,889,654 La Fever June 9, 1959 2,977,666 Brace et a1.Apr. 4, 1961 2,981,023 Sergay Apr. 25, 1961

1. IN A REVOLVER FIREARM HAVING A FRAME, A BARREL, A CYLINDER ROTATABLY MOUNTED IN SAID FRAME, SAID CYLINDER HAVING A PLURALITY OF CHAMBERS FORMED THEREIN FOR RECEIVING CARTRIDGES, THE ROTATION OF SAID CYLINDER BRINGING SAID CHAMBERS SUCCESSIVELY INTO ALIGNMENT WITH SAID BARREL, THE FORWARD END OF SAID CYLINDER BEING SPACED FROM THE REAR END OF SAID BARREL BY A GAP THROUGH WHICH PROPELLANT GASES FROM SAID CARTRIDGES PASS; THE IMPROVEMENT WHICH COMPRISES SAID FRAME HAVING A PORTION BRIDGING A PART OF SAID GAP BETWEEN SAID BARREL AND SAID CYLINDER, SAID BRIDGING PORTION BEING SUBSTANTIALLY HARDER THAN THE REMAINDER OF THE FRAME FOR RESISTING EROSION BY SAID PROPELLANT GASES, SAID GAP BEING OPEN FOR THE PASSAGE OF SAID GASES OUTWARDLY THROUGH SAID GAP TO THE SPACE AROUND SAID BARREL AND CYLINDER SO THAT A PORTION OF SAID GASES CONTACTS SAID HARDER BRIDGING FRAME PORTION. 